EXHIBIT 10.4

                         KERYX BIOPHARMACEUTICALS, INC.

                      2002 CEO INCENTIVE STOCK OPTION PLAN
                   SPECIAL NONSTATUTORY STOCK OPTION AGREEMENT

1. Grant of Option.

      This Agreement evidences the grant by Keryx Biopharmaceuticals, Inc., a
Delaware corporation (the "Company"), on December 23, 2002 (the "Grant Date") to
Michael S. Weiss, Chairman and Chief Executive Officer of the Company (the
"Executive"), of an option to purchase (the "Option"), in whole or in part, on
the terms provided herein, and on the terms provided in the Employment Agreement
dated as of December 23, 2002, between the Company and the Executive (the
"Employment Agreement"), a total of 2,002,657 shares (the "Shares") of common
stock, $0.001 par value per share, of the Company (the "Common Stock") at $1.30
per share (the "Option Price"). Unless earlier terminated, this Option shall
expire on December 23, 2012 (the "Final Exercise Date"). It is intended that the
Option shall not be an incentive stock option as defined in Section 422 of the
Internal Revenue Code of 1986, as amended (the "Code").

2. Vesting Schedule.

      (a) Regular Vesting. Subject to the provisions of subsection 2(b), below,
the Option shall become exercisable ("vest") as follows:

            (i)   the Option to purchase all of the Shares shall vest on
                  December 23, 2009 , provided that the Executive is employed on
                  that date as Chairman and/or Chief Executive Officer and/or a
                  director of the Company.

            (ii)  Notwithstanding subsection 2(a)(i) above, the exercisability
                  of the Option to purchase 652,657 of the Shares shall be
                  accelerated in full upon the occurrence of the earlier of:

                  a.    The Company achieving a total market capitalization on a
                        fully diluted basis of more than five hundred million
                        dollars ($500,000,000) (including shares attributable to
                        all outstanding shares, options, warrants, other
                        purchase rights and convertible securities, and
                        including shares held by affiliates collectively "Fully
                        Diluted Shares"), as determined by the following
                        formula: Fully Diluted Shares multiplied by the average
                        of the Fair Market Value (as defined below) of the
                        common stock for three consecutive trading days plus
                        long-term liabilities minus Working Capital (as defined
                        below) and minus the aggregate exercise price of all
                        options and warrants included in the Fully Diluted
                        Shares; or

                  b.    The Company possessing at least one hundred million
                        dollars ($100,000,000) in "Working Capital" (which shall
                        mean as of any date, the current assets plus investment
                        securities or similar assets which have maturities in
                        excess of 12 months less current liabilities).

            (iii) Notwithstanding subsection 2(a)(i) above, the exercisability
                  of the Option to purchase 1,350,000 of the Shares shall be
                  accelerated in full upon the occurrence of the earlier of:

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                  a.    The Company achieving a total market capitalization on a
                        fully diluted basis of more than one billion dollars
                        ($1,000,000,000), as determined by the following
                        formula: Fully Diluted Shares multiplied by the average
                        of the Fair Market Value of the common stock for three
                        consecutive trading days plus Long-term Debt minus
                        Working Capital and minus the aggregate exercise price
                        of all options and warrants included in the Fully
                        Diluted Shares; or

                  b.    The Company possessing at least one hundred and fifty
                        million dollars ($150,000,000) in Working Capital.

      (b) Accelerated Vesting. Upon the earlier to occur of (i) a Change of
Control or Reorganization Event, each as defined below, or (ii) upon termination
of the Executive's employment for any reason, including, without limitation, as
a result of the Executive's death or Disability (as defined below) other than
(A) for Cause by the Company (as defined in the Employment Agreement) or (B)
without Good Reason by the Executive (as defined in the Employment Agreement),
the vesting schedule with respect to the Option shall be accelerated so that the
Option shall become vested and exercisable as to all of the Shares that would
otherwise have first become exercisable on any vesting date scheduled to occur
on or after such Change of Control or Reorganization Event or termination of the
Executive's employment, as the case may be, (x) as of a specified time prior to
the Reorganization Event or Change of Control in such a manner as to allow the
Executive and/or Permitted Transferees to take part in such Reorganization Event
or Change of Control on the same terms as other holders of Common Stock; or (y)
immediately upon the effective date of the termination of the Executive's
employment, as the case may be. Additionally, the Board of Directors shall have
the discretion to accelerate the vesting of all or a portion of the Option at
any time.

      (c) Definitions. For the purposes of this Agreement:

            (i)   A "Reorganization Event" shall mean:

                  (A)   any merger or consolidation of the Company with or into
                        another entity as a result of which all of the Common
                        Stock of the Company is converted into or exchanged for
                        the right to receive cash, securities or other property;
                        or

                  (B)   any exchange of all of the Common Stock of the Company
                        for cash, securities or other property pursuant to a
                        share exchange transaction.

            (ii)  A "Change in Control Event" shall mean:

                  (A)   the acquisition by an individual, entity or group
                        (within the meaning of Section 13(d)(3) or 14(d)(2) of
                        the Exchange Act) (a "Person") of beneficial ownership
                        of any capital stock of the Company if, after such
                        acquisition, such Person beneficially owns (within the
                        meaning of Rule 13d-3 promulgated under the Exchange
                        Act) 30% or more of either (I) the then-outstanding
                        shares of common stock of the Company (the "Outstanding
                        Company Common Stock") or (II) the combined voting power
                        of the then-outstanding securities of the Company
                        entitled to vote generally in the election of directors
                        (the "Outstanding Company Voting Securities"); provided,
                        however, that for purposes of this subsection (A), the
                        following acquisitions shall not constitute a Change in
                        Control Event: (1) any


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                        acquisition directly from the Company (excluding an
                        acquisition pursuant to the exercise, conversion or
                        exchange of any security exercisable for, convertible
                        into or exchangeable for common stock or voting
                        securities of the Company, unless the Person exercising,
                        converting or exchanging such security acquired such
                        security directly from the Company or an underwriter or
                        agent of the Company), (2) any acquisition by any
                        employee benefit plan (or related trust) sponsored or
                        maintained by the Company or any corporation controlled
                        by the Company, (3) any acquisition by any corporation
                        pursuant to a Business Combination (as defined below)
                        which complies with clauses (I) and (II) of subsection
                        (C) of this definition, or (4) any acquisition by
                        Lindsay A. Rosenwald, Paramount Capital, Inc., or any
                        entity controlled by, controlled or under common control
                        with Paramount Capital, Inc. (each such party is
                        referred to herein as an "Exempt Person") of any shares
                        of capital stock of the Company.

                  (B)   such time as the Continuing Directors (as defined below)
                        do not constitute a majority of the Board (or, if
                        applicable, the Board of Directors of a successor
                        corporation to the Company), where the term "Continuing
                        Director" means at any date a member of the Board (I)
                        who was a member of the Board on the date of the initial
                        adoption of this Plan by the Board or (II) who was
                        nominated or elected subsequent to such date by at least
                        a majority of the directors who were Continuing
                        Directors at the time of such nomination or election or
                        whose election to the Board was recommended or endorsed
                        by at least a majority of the directors who were
                        Continuing Directors at the time of such nomination or
                        election; provided, however, that there shall be
                        excluded from this clause (II) any individual whose
                        initial assumption of office occurred as a result of an
                        actual or threatened election contest with respect to
                        the election or removal of directors or other actual or
                        threatened solicitation of proxies or consents, by or on
                        behalf of a person other than the Board; or

                  (C)   the consummation of a merger, consolidation,
                        reorganization, recapitalization or share exchange
                        involving the Company or a sale or other disposition of
                        all or substantially all of the assets of the Company (a
                        "Business Combination"), unless, immediately following
                        such Business Combination, each of the following two
                        conditions is satisfied: (I) all or substantially all of
                        the individuals and entities who were the beneficial
                        owners of the Outstanding Company Common Stock and
                        Outstanding Company Voting Securities immediately prior
                        to such Business Combination beneficially own, directly
                        or indirectly, more than 50% of the then-outstanding
                        shares of common stock and the combined voting power of
                        the then-outstanding securities entitled to vote
                        generally in the election of directors, respectively, of
                        the resulting or acquiring corporation in such Business
                        Combination (which shall include, without limitation, a
                        corporation which as a result of such transaction owns
                        the Company or substantially all of the Company's assets
                        either directly or through one or more subsidiaries)
                        (such resulting or acquiring corporation is referred to
                        herein as the "Acquiring Corporation") in substantially
                        the same proportions as their ownership of the
                        Outstanding Company Common Stock and Outstanding


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                        Company Voting Securities, respectively, immediately
                        prior to such Business Combination; and (II) no Person
                        (excluding Exempt Persons, the Acquiring Corporation or
                        any employee benefit plan (or related trust) maintained
                        or sponsored by the Company or by the Acquiring
                        Corporation) beneficially owns, directly or indirectly,
                        30% or more of the then-outstanding shares of common
                        stock of the Acquiring Corporation, or of the combined
                        voting power of the then-outstanding securities of such
                        corporation entitled to vote generally in the election
                        of directors (except to the extent that such ownership
                        existed prior to the Business Combination).

            (iii) "Fair Market Value" shall mean, as of any date, the value of a
                  a share of Common Stock of the Company determined as follows:

                  (A)   If the shares of Common Stock are listed on any
                        established stock exchange or a national market system,
                        including without limitation the Nasdaq National Market
                        or the Nasdaq SmallCap Market of the Nasdaq Stock
                        Market, Fair Market Value shall be the closing sales
                        price for such shares (or the closing bid, if no sales
                        were reported) as quoted on such exchange or system for
                        the last full market trading day immediately prior to
                        the time of determination as reported in The Wall Street
                        Journal or such other source as the Administrator deems
                        reliable;

                  (B)   If the shares of Common Stock are regularly quoted by a
                        recognized securities dealer but selling prices are not
                        reported, Fair Market Value shall be the mean between
                        the high bid and low asked prices for such shares on the
                        last full market trading day immediately prior to the
                        day of determination; or

                  (C)   In the absence of an established market for the shares
                        of Common Stock, Fair Market Value thereof shall be
                        determined in good faith by the Administrator.

            (iv)  "Disability" shall mean a situation wherein the Executive is
                  unable, due to any physical or mental disease or condition, to
                  perform his normal duties of employment for 120 consecutive
                  days or 180 days in any twelve-month period.

      (d) The right of exercise shall be cumulative so that to the extent the
Option is not exercised in any period to the maximum extent permissible it shall
continue to be exercisable, in whole or in part, with respect to all Shares for
which it is vested until the earlier of the Final Exercise Date or the
termination of this Option under Section 3 hereof.


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3. Exercise of Option.

      (a) Method of Exercise. Subject to the conditions set forth herein, this
Option may be exercised from time to time by delivery of written notice of
exercise to the Company from the Executive or a Permitted Transferee. Such
notice shall specify the total number of Shares to be purchased and shall be
accompanied by payment in full (or an arrangement for payment in full) in
accordance with Section 3(b) below. Such exercise shall be effective upon
delivery to the Company of such written notice together with the required
payment (or arrangement for payment). This option may be exercised for less than
the full number of Shares for which it is then exercisable, provided that no
such exercise may be for any fractional Share.

      (b) Method of Payment. Payment of the purchase price for Shares purchased
upon an exercise of this Option may be made: (i) by delivery to the Company of
cash, a wire transfer of available funds, or a check payable to the order of the
Company and backed by sufficient funds, in each case in an amount equal to the
purchase price of such Shares; (ii) by delivery to the Company of shares of the
Company then owned by the Executive having an aggregate Fair Market Value as of
the date of delivery equal to the purchase price of the Shares being purchased
upon the exercise of this Option, provided that the shares being delivered in
payment for such Shares have been held by the Executive for at least six (6)
months or have such other characteristics such that the use of such shares does
not result in an accounting charge to the Company; (iii) if allowed by
applicable law, through reasonable cashless exercise procedures that are from
time to time established or approved by the Company and that afford the
Executive the opportunity to sell immediately some or all of the Shares
underlying the exercised portion of this Option in order to generate sufficient
cash to pay the option purchase price, provided that the Company shall not
unreasonably delay establishing, or approving, such procedures upon reasonable
request by the Executive; (iv) in the event that the Company elects to account
for this Option in accordance with FAS 123 such that payment in the following
fashion does not change the manner of accounting for this Option were the
payment of the exercise price in cash, by authorizing the Company to withhold
Shares that would otherwise be delivered on such exercise having a Fair Market
Value on the date of exercise equal to the amount of the purchase price; (v) if
allowed by applicable law, by delivering to the Company a full recourse
three-year promissory note which shall (A) bear interest, payable at maturity,
at the applicable federal rate (as defined in and under Section 1274(d) of the
Code), and (B) be secured by a pledge of the Shares delivered on such exercise,
subject to the right of the Executive or his Permitted Transferee to sell such
Shares and remit the after-tax proceeds of such sale to the Company in repayment
of such note; or (vi) by any combination of (i), (ii), (iii), (iv) or (v).

      (c) Delivery of Shares Tendered in Payment of Purchase Price. Payment by
delivery of Shares may be effected by delivering one or more stock certificates
or by otherwise delivering Shares to the Company's reasonable satisfaction
(including, without limitation, through an "attestation" procedure that is
reasonably acceptable to the Company), in each case accompanied by such
endorsements, stock powers, signature guarantees or other documents or
assurances as may reasonably be required by the Company. If a certificate or
certificates or other documentation representing Shares in excess of the amount
required are delivered, a certificate (or other satisfactory evidence of
ownership) representing the excess number of Shares shall promptly be returned
by the Company.

      (d) Delivery of Option Shares. The Company shall, upon payment in
accordance with Section 3(b) above of the aggregate purchase price for the
number of Shares purchased, make prompt delivery of such Shares to the Executive
or Permitted Transferee and pay all original issue and transfer taxes and all
other fees and expenses incident to such delivery. All Shares delivered upon any
exercise of this option shall, when issued in accordance with the terms of this
Agreement and delivered: (i) be duly authorized, validly issued, fully paid and
nonassessable; (ii) be registered, or otherwise qualified, for sale, and for
resale, under state and Federal securities laws to the extent that other Shares
of the same class are then so registered or qualified; provided, however, that
in no event shall the Company be required to prepare and file a Form S-3 reoffer
prospectus in respect of such Shares prior to the


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earlier of (A) 18 months following the date hereof or (B) immediately prior to
the exercise by the Executive or his Permitted Transferee of all or any portion
of this Option; and (iii) be listed, or otherwise qualified, for trading on any
securities exchange or securities market on which Shares of the same class are
then listed or qualified. To the extent that Shares are not promptly delivered
to the Executive or Permitted Transferee (as the case may be) when due as a
result of any action or inaction by the Company, the Company shall promptly make
the Executive or Permitted Transferee whole for any resulting expense or loss of
benefit. The Company shall deliver cash in lieu of any fractional Share.

      (e) Termination of Relationship as a Service Provider. Unless the Board of
Directors or any committee charged with administering this Agreement (the
"Administrator") determines that a longer period is applicable or such longer
period is otherwise set forth in this paragraph, if the Executive ceases to be
an employee, director or consultant of the Company (a "Service Provider"), other
than upon the Executive's death or Disability, the Executive, or his Permitted
Transferee, may exercise the Option within a one (1) year period following his
termination to the extent that the Option is vested on the date of termination
(but in no event later than the Final Exercise Date). Notwithstanding the
foregoing, (i) should the Executive's termination be by the Company for Cause,
such period shall be for a length of thirty (30) days following the Executive's
termination; and (ii) should the Executive's employment be terminated on the
account of his death, on account of Disability, by the Company without Cause, or
by the Executive for Good Reason, the Executive, or his Permitted Transferee, as
applicable, may exercise the Option within a period of two (2) years following
such termination (but in no event later than the Final Exercise Date). If, on
the date of termination, the Executive is not vested as to the entire Option
(after taking into account paragraph 2(b) above), the unvested portion shall not
be exercisable and the unvested portion of the Option shall be cancelled. If,
after termination, the Executive, or his Permitted Transferee, as applicable,
does not exercise the portion of the Option that had vested within the time
specified by this Agreement or the Administrator, such vested portion of the
Option shall terminate.

      (f) Buyout Provisions. The Administrator may at any time, if permitted
under applicable laws, offer to buy out the Option for a payment in cash or
Shares, based on such terms and conditions as the Administrator shall establish
and communicate to the Executive at the time that such offer is made. No such
offer shall obligate the Executive to relinquish the Option.

4. Taxes and Withholding.

      No Shares will be issued pursuant to the exercise of this Option unless
and until the Executive or a Permitted Transferee pays to the Company, or makes
provision satisfactory to the Company for payment of, any federal, state or
local withholding taxes required by law to be withheld in respect of this
Option. The Executive or Permitted Transferee may satisfy any such tax
obligations in the manner provided in Section 3(b)(i) or (ii), above, for
payment of the purchase price, or by electing to have Shares withheld from the
exercise of this Option having a Fair Market Value equal to the amount of such
tax obligations.


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      Furthermore, the Executive hereby agrees to indemnify the Company and hold
it harmless against and from any and all liability for any such tax or interest
or penalty thereon, including without limitation, liabilities relating to the
necessity to withhold, or to have withheld, any such tax from any payment made
to the Executive or a Permitted Transferee. Transfer of the Option, or any
portion thereof, shall be conditional upon the execution of an agreement whereby
the Permitted Transferee assumes the obligations of indemnification set forth in
this paragraph.

5. Transferability of the Option.

      The Option granted hereunder shall not be transferable by the Executive
other than by will or by the laws of descent and distribution. Notwithstanding
the foregoing, the Option, or any portion thereof, may be transferred without
consideration to members of the Executive's immediate family, to trusts for the
benefit of such family members, to partnerships in which such family members are
the only partners and to charities (including the Executive's estate, the
"Permitted Transferees"). The Option may be exercised during the Executive's
lifetime only by the Executive, or his guardian or legal representative, or a
Permitted Transferee.

6. Conditions on Delivery of Stock.

      (a) Legal Compliance. Shares shall not be issued pursuant to the exercise
of the Option unless the exercise of the Option, the method of payment and the
issuance and delivery of such Shares shall comply with applicable laws and shall
be further subject to the approval of counsel for the Company with respect to
such compliance.

      (b) Inability to Obtain Authority. The inability of the Company to obtain
authority from any regulatory body having jurisdiction, which authority is
deemed by the Company's counsel to be necessary to the lawful issuance and sale
of any Shares hereunder, shall relieve the Company of any liability in respect
of the failure to issue or sell such Shares as to which such requisite authority
shall not have been obtained. The Company shall use its best efforts to remedy
such inability to gain authority as soon as reasonably possible.

7. Adjustments.

      (a) Changes in Capitalization. Subject to any required action by the
stockholders of the Company, the number of Shares covered by or underlying the
Option, as well as the exercise price per Share of the Option shall be
proportionately adjusted for extraordinary cash dividends and for any increase
or decrease in the number of issued Shares resulting from a share split, reverse
share split, share dividend, recapitalization, combination or reclassification
of the Shares, rights issues or any other increase or decrease in the number of
issued Shares effected without receipt of consideration by the Company;
provided, however, that conversion of any convertible securities of the Company
shall not be deemed to have been "effected without receipt of consideration."
Such adjustment shall be made by the Administrator, whose determination shall be
final, binding and conclusive. Except as expressly provided herein, no issuance
by the Company of shares of any class, or securities convertible into shares of
any class, shall affect, and no adjustment by reason thereof shall be made with
respect to, the number or price of the Shares subject to the Option.


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      (b) Dissolution or Liquidation. In the event of the proposed dissolution
or liquidation of the Company, the Administrator shall notify the Executive and
each Permitted Transferee as soon as practicable prior to the effective date of
such proposed transaction. The Administrator in its sole discretion may provide
for the Executive and each Permitted Transferee to have the right to exercise
this Option until fifteen (15) days prior to such transaction as to all of the
Shares, including Shares as to which the Option would not otherwise be
exercisable. To the extent it has not been previously exercised, this Option
will terminate immediately prior to the consummation of such proposed
transaction.

      (c) Reorganization and Change in Control Events. Upon the occurrence of a
Reorganization Event or a Change in Control, or the execution by the Company of
any agreement with respect to a Reorganization Event or a Change in Control, the
Board shall provide that the portion of the Option that is outstanding shall be
assumed, or equivalent options shall be substituted, by the acquiring or
succeeding corporation (or an affiliate thereof). For purposes hereof, the
Option shall be considered to be assumed if, following consummation of the
Reorganization Event or Change of Control, the new options confer the right to
purchase, for each share of Common Stock subject to the Option immediately prior
to the consummation of the Reorganization Event or Change of Control, the
consideration (whether cash, securities or other property) received as a result
of the Reorganization Event or Change of Control by holders of Common Stock for
each share of Common Stock held immediately prior to the consummation of the
Reorganization Event or Change of Control (and if holders were offered a choice
of consideration, the type of consideration chosen by the holders of a majority
of the outstanding shares of Common Stock); provided, however, that if the
consideration received as a result of the Reorganization Event or Change of
Control is not solely common stock of the acquiring or succeeding corporation
(or an affiliate thereof), the Company may, with the consent of the acquiring or
succeeding corporation, provide for the consideration to be received upon the
exercise of the Option to consist solely of common stock of the acquiring or
succeeding corporation (or an affiliate thereof) equivalent in fair market value
as determined in good faith by the Board to the per share consideration received
by holders of outstanding shares of Common Stock as a result of the
Reorganization Event or Change of Control.

8. Continuation of Employment.

      Neither this Agreement nor the Option shall confer upon the Executive any
right to continued employment by (or any other relationship with) the Company or
any subsidiary, affiliate or parent thereof, or limit in any respect the right
of the Company to terminate the Executive's employment or other relationship
with the Company or any subsidiary, affiliate or parent thereof, as the case may
be, at any time.

9. Stockholder Rights.

      No person or entity shall have any rights as a stockholder with respect to
any shares of Common Stock to be distributed with respect to this Option until
becoming the record holder of such shares.

10. Construction.

      This Agreement shall be interpreted consistent with the terms of the
Employment Agreement.


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11. Governing Law.

      This Agreement shall be governed by and construed in accordance with the
laws of the State of Delaware, but without regard to the principle of conflict
of laws thereof. If any one or more provisions of this Agreement shall be found
to be illegal or unenforceable in any respect, the validity and enforceability
of the remaining provisions hereof shall not in any way be affected or impaired
thereby.

12. Successors and Assigns.

      This Agreement shall inure to the benefit of and be binding upon the
Executive, the Company, their respective beneficiaries, heirs, executors,
administrators, legal representatives and guardians, and their permitted
successors and assigns.

13. Notices.

      All notices and other communications required or permitted hereunder shall
be in writing and deemed to have been received on the date of delivery if
delivered by hand or overnight express, or three days after the date of posting
if mailed by registered or certified mail, postage prepaid, addressed to the
Company at 750 Lexington Avenue, New York, New York 10022, and to the Executive
at 300 East 77th Street, NY, NY 10021 (or such other address to which the
Company or the Executive hereby notifies the other party hereto to send such
notices and communications). Such notices and other communications shall not be
considered delivered until actually received or deemed received pursuant to this
Section 13.

14. Amendment of Option.

      No amendment, alteration, suspension or termination of the Option shall
impair the rights of the Executive, unless mutually agreed otherwise between the
Executive and the Company, which agreement must be in writing and signed by the
Executive and the Company.

15. Reservation of Shares

      The Company, during the term of this Agreement, shall at all times reserve
and keep available and authorized for issuance such number of Shares as shall be
sufficient to satisfy the requirements of


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      the Option.

      IN WITNESS WHEREOF, the Company has caused this option to be executed
under its corporate seal by its duly authorized representative. This Option
shall take effect as a sealed instrument.

                                        KERYX BIOPHARMACEUTICALS, INC.


                                        By:  /s/ Lindsay A. Rosenwald
                                             -----------------------------------
                                        Name:  Lindsay A. Rosenwald
                                        Title:  Director

AGREED TO AND ACCEPTED BY:

EXECUTIVE


/s/ Michael S. Weiss
----------------------------
Michael S. Weiss

Address: 300 East 77th Street
         New York, NY 10021


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